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A spin index, which has 360 divisions will not come out even (360/14 = 25.71...). But a winding ratchet does not have to be very precise so you could round to the nearest degree and it would work. In fact you would be hard pressed to notice the differences. Here is a table you could follow. The worst error is 0.43 degree.

0
26
51
77
103
129
154
180
206
231
257
283
309
334
360

If you have an indexing head or rotary table that has any gear ratio that is even (1:40 or 1:90 are common ones), then you can use any hole circle that has any multiple of 7 holes: 7, 14, 21, 28, etc. If you can provide the details, I/we can advise on turns and holes per division.

If you have neither of the above, you can use a paper scale as suggested above. Any CAD program can compose and print a suitable scale. Again, for a winding ratchet, a lot of precision is not really needed.

Yep, in fact that is how some of the old clock/watch makers would have done it. Scratch a circle. Set the dividers with a good (or bad) guess. Step around that circle and observe the error. Make a correction and try again. Repeat until you can not see any further error.

Not super precise, but it will work.

Stop worrying about it and just do it.

Originally Posted by JoeCB

We are over - thinking this ! It's a simple ratchet not a cog wheel and in brass at that. How about a pair of dividers and a file.

Yep, in fact that is how some of the old clock/watch makers would have done it. Scratch a circle. Set the dividers with a good (or bad) guess. Step around that circle and observe the error. Make a correction and try again. Repeat until you can not see any further error.

Not super precise, but it will work.

Stop worrying about it and just do it.

That is actually a pretty precise way to map out a bolt circle.

I was gonna suggest that but it seemed like Brett wanted to use another method. JR

Most spring winding ratchets don't have to be terribly precise. I've made one of these and used it to make plastic gears for my mini mill and mini lathe. It should be pretty easy to adapt it to a ratchet wheel using just a straight milling cutter set to mid point on the blank. Make shallow cut, turn blank, make next cut.